Much water has passed under the bridge of modern ventilation practice, and with it comes the installation of the latest bandwidth control equipment that can manage temperature and other parameters within a predefined range. Farmers have found the concept hasn’t been cheap to install, but bandwidth control does two important things:
- It takes the onus off the producer and his staff to get things exactly right over the pigs (temperature, air movement and air quality) at all times. This can be done with existing manual methods, but it’s laborious, and what about 10pm to 6am when the staff are absent? Literally, in modern parlance, bandwidth, properly programmed, works 24/7.
- Farmers and their stockpeople are only too well aware of the many things continuously changing environmentally outside (temperature, wind speed and direction) and managementally inside (stocking density, feed intake and humidity) that demand alterations to the operating controls. Neither do they need telling that not to do so frequently affects the pig’s performance and health. Over the years, they’ve become practised at setting and then re-adjusting the controls to cope with at least some of these variations.
A trial – one against the other
I say “some of” the variations because, despite the diligent attention to setting controls and making adjustments where needed, hand-set alterations can never be ideal. For example, when I forced myself to spend the night with the pigs, I discovered readings can change markedly in the hours of darkness. To illustrate this point, when I found a co-operative grower/finisher who was updating his ventilation and had decided to use bandwidth technology, I asked him to delay changing one house over to bandwidth so as to run a concurrent trial with his existing system. Pigs, layout and feeding were exactly the same, and 20 replicates of 12 pigs/pen were put by for the trial. Some very interesting results emerged which I will describe next time. Coughing incidence came into it, as you will see. A lot less coughing on bandwidth. But why?
I’ve always been keen on studying coughing in pigs, which started from my days as a rookie stockman in those new-fangled nurseries (yes – it was that long ago!). I was made to go down last thing at night and check their breathing by opening the door just a fraction and listening. As my wise old boss told me, “You can detect possible trouble ahead, stomach troubles and respiratory disease – just by recognising any signs of laboured breathing, teeth grinding and what my Scots companions call “girning”. After a week or so, I thought I would try opening the door and switching on the light just have a look at them. This stirred them up, and any ticklish lungs resulted in coughing. Too much of it and our vet was consulted.
I then began to get interested in the different types of coughing.
Those of you who’ve accompanied me on farms will have seen what I do and some probably think it fanciful. It isn’t. I never enter a nursery or grower house today without telling my companions to please stop talking and keep quiet while I listen to the pigs behaving normally and unaware of me – and then entering to get their attention, stirring them up, listening for coughing – I can learn a lot from this. So many farm advisers crash-bash straight into a house and so miss the difference between unobserved behaviour and alertness – or lack of it sometimes. Listening for undue coughing and recognising the different types is a part of this observation.
Science now taking an interest
This is why I’m delighted that coughing incidence is being studied scientifically at the Prairie Research Group in Alberta – they do such practical trial work, bless them – and also by fascinating Telephone Recording work in the Netherlands. Now commercially available, it’s suggested that swine flu, M Pneumonia and PRRS can be picked up as much as three weeks sooner – and your vet knows what that’s worth.
CLICK HERE for John’s next instalment on bandwith ventilation